Sewing-machine



(No Model.)

B. T. THOMAS Sewing Machine.

Patented April 26,1881,-

N- PETERS, PHOTO-UTMOGRAPHER, WASHINGTON, D. C.

PATENT OFFICE.

EDDYT. THOMAS, OF NEW YORK, N. Y., ASSIGNOR TO THE GOLD MEDAL SEWING MACHINE COMPANY, OF ORANGE, MASSACHUSETTS.

SEWING-MACHINE,

SPECIFICATION forming part of Letters Patent No. 2 40,563, dated April 26, 1881.

Application filed November 11, 1880. (No model.)

To all whom ct may concern Be it known that I, EDDY T. THOMAS, of the city, county, and State of New York, have invented an Improvementin Sewing-Machines,

of which the following description, in connection with the accompanying drawings, is a,

specification.

This invention in sewing-machines has for one of lts objects an organization of parts for operating a horizontally-vibrating shuttle-carrying lever and a feed-actuating rocker-shaft from the rotating needle-shaft by the intervention of one single forked lever having onlya movement of vibration abouta center. My invention also relates to means for operatin g the usual four-motioned feed from the said rocker-shaft by means of a pawl-andratchet connection between the said rockershat't and a feed-operating cam-block which is of peculiar construction, as will appear hereinafter.

Prior to this invention a vibrating shuttlecarrying lever and a rotating feed-operating shaft have been actuated from an eccentric on bar, the said eccentric moving a link slotted between its ends to both rock and slide on a fixed fulcrum.

By employing with the needle-operating shaft a forked lever having only a movement of vibration I am enabled to make use of a rock-shaft to actuate the four-motioned feed-- moving cam-block, thus making the movement of the parts as little as possible and with the least amount of friction and strain.

Figure 1 represents, in vertical section, a sufficient portion of a sewing-machine to ex plain my invention Fig. 2, a detail of the lower end of the vertically-placed forked lever connecting the upper rotary needle-bar-open ating shaft with the shuttle-lever and feed-act- .uating rockshaft Fig. 3, apartial under-side view, illustrating the feed-actuating rock-shaft and feed-block and feed-bar moved by it Fig. 4., a section on the line mm, Fig. 1, showing the feed; Figs. 5 and 6, sections, respectively, on the lines 3 and 2, Fig. 4; Fig. 7, a detail, in plan view, of the feed-regulating device 5 Fig.

l. 8, a sectional detail of Fig. 7 on the dotted line 50 00 Fig. 9 is a detail of the upper end of the the rotating shaft which actuates the needle said blocks are placed.

vertically-placed forked lever which, embraces the needle-shaft.

The frame-work aof the machine, including the overhanging arm a rotating needle-bar-opcrating shaft 01?, aud fly-wheel a, are all of usual construction. The shaft a has an eccentric,

. a which is embraced by the open forked upper end of the vertically-placed lever b, pivoted on the fulcrum b',,so as to vibrate thereon, the lower end of the said lever moving in the arc of a circle the center of which is the fulcrum b or, in other words, the said lever does not reciprocate as it is vibrated, as would be necessary were the end of the lever 12' provided with a strap to embrace the eccentric rather than with the open fork. Thislever b, below its pivot, is slotted or recessed to receive within it two slide-blocks, b b of a length less than thelength of the slots. These blocks receive between them the ball-like or rounded end 2 of the short arm of the horizontally-vibrating shuttle-carryin g lever d, of usual construction, it being pivoted upon avertical stud,

d, the said lever, in practice, being provided at its front end with a shuttle-carrier, as in the well-known Domestic machine. These blocks b b as the levers b and d are vibrated, are permitted to slide for a short distance vertically in the recess in the lever b, in which the The lower end of the lever 12 has a ball-like end, 4, entered between blocks'b b placed between the cheeks 5; of a crank-arm, 0, attached to the feedoperating rock-shaft 6, held in suitable bearings, 6 the said blocks 11 b sliding between the said checks as thelower end of the lever b, during its vibrations, rocks the shaft 6. At its forward end this rock-shaft has an arm, a which, as the shaft 6 is rocked, causes a spring-pawl, 0, carried by the said arm a to engage the ratchet 6?, forming part of the camblock f, placed loosely on the shaft e held in bearings 6, the pawl and ratchet moving, as herein shown, the said ratchet and block onefourth a rotation at each movement of the rockshaft. This feed-operating cam-block f, placed loosely on the shaft 6 at right angles to the rock-shaft 0, has at one end (see Figs. 4 and 5) cam faces 7, four being shown, to operate against the leg 8 of the feed bar 9 and move 10o the feed-bar forward once for each one with rotation of the said block. The feed-bar is guided on' the pin or stud 9. The periphery of this block is cut away or depressed to form four inclined surfaces, 10, upon which the short leg 12 at the under side of the feed-bar g rests and slides as the said feed-bar is moved forward and backward by the face or end cams, 7, of the intermittingly-rotated block.

The spiral spring 13 acts to keep the leg 8 of the feed-bar against the cam-faces 7 The length of the block is in excess of the length of feed-stroke and stitch, and each portion,

of its periphery included between an arc of ninety degrees is so inclined or shaped as by its action on the leg 12, which rests directly upon one of the said cam-surfaces 10 during the entire reciprocations of the feed bar g, to lift the serrated end of the feed-bar in contact with the fabric just before it is to be moved forward, hold the said serrated portion in contact with the fabric while the feed-bar is moved to feed the fabric, and then to let the feed-bar drop from the fabric, while the latter is left at rest and the feed bar, removed from contact with it, is moved backward below the fabric by a suitable spring. The feed-bar g is always moved forward to the same point and backward to a variable point, according to the length of stitch. Variation in the length of stitch is provided for by the sliding or moving wedge i, in-

chine-plate, and cooperating with any usual index.

I claim- 1. In a sewing-machine, the rotating needleoperating shaft and eccentric thereon, the rocker-shaft 0, adapted to operate the feed, and the horizontally vibrating shuttle carrying lever, combined with the vertically placed forked and pivoted lever provided with the recess to receive the end of the shuttle-lever, and connected at its lower end with the arm of the rocker-shaft, the lower end of the said forked lever vibrating in the arc of a circle described from the center of the stud or fulcrum of the said lever, and by its loose connection vibratin g the shuttle-lever and rocking the said shaft 0, all substantially as described.

2. The shaft 0 and means to rock it, its arm e and pawl, and the ratchet and block, provided at its end with cam-faces 7 and at its periphery with cam-surfaces 10, combined with the feed bar having legs 8 and 12, to rest against the faces? and surfaces 10 of the said block, to operate substantially as described.

, 3. In a sewing-machine, the feed-bar and its legs 8 and 12, combined with a cam-block having cam surfaces and faces, to act against the said legs to lift and move the feed forward, and with means to move the cam block intermittingly, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

EDDY T. THOMAS.

Witnesses:

SPENCER C. Dory, BERNARD J. KELLY. 

